sshkeeper v0.7.3

sshkeeper v0.7.3 — safe migration of legacy synchronized key paths

v0.7.3 includes all Windows and portable-key fixes from v0.7.2 and adds one
upgrade safeguard for devices that already synchronized with v0.7.0/v0.7.1.

Fixed

• Existing Windows clients keep legacy key records during migration. If a
  profile still points to an old Linux absolute path such as
  /home/alice/.ssh/id_ed25519, the first v0.7.3 sync protects that legacy
  record from being interpreted as a local deletion before the remote key can
  be materialized under the Windows user's .ssh directory.
• Both the legacy absolute-path record ID and its new portable
  ~/.ssh/... record ID are treated as unreadable-but-existing during that
  transition, so the remote key survives the merge and can be copied locally.

Upgrade

No re-pairing or database migration is required. Upgrade both sides as usual
and run synchronization once. Profiles and key files are migrated in place.